textproduct: Albany

WHAT HAS CHANGED

A slight to low chance of showers and a few thunderstorms was expanded across the forecast area late Sun/Sun night with an upper level disturbance.

Will continue to monitor trends for the potential for some strong to potentially severe thunderstorms towards the mid week.

KEY MESSAGES

1) Mainly dry and seasonable weather is expected for most of the weekend across eastern NY and western New England.

2) Multiple rounds of showers and thunderstorms are likely next week due to a stalled frontal boundary with the potential for some strong to severe thunderstorms towards Wednesday.

DISCUSSION

KEY MESSAGE 1... High pressure continues to ridge in from southeastern Ontario and the eastern Great Lakes Region this morning with cool temps and some patchy fog especially north and west of the Capital District with the clear skies and light to calm winds. The radiative mist/fog should burn off quickly with the strong subsidence associated with the anticyclone for seasonable temps near to slightly below normal for late August. Max temps were accepted close to the NBM with highs in the mid to upper 70s in the major valleys and mid 60s to lower 70s over the hills and mtns. Another cool night is expected with lows in the upper 40s to mid 50s, but some mid and high clouds will increase Sat night into Sun morning.

In the west northwest flow aloft, a short-wave will bring some isolated-scattered showers and a few thunderstorms across the western Adirondacks and a separate batch south of the Capital Region during the afternoon on Sunday. We expanded the coverage of showers/isolated thunderstorms across the entire forecast area Sunday night, as the short-wave moves through. If faster trends continue on the CAMs and short-range guidance, then we may have to expand the coverage of scattered showers/isolated t-storms Sunday afternoon. The latest HREF shows mean SBCAPEs mainly below 500 J/kg which will limit updraft heights with 0-6 km shear 30-35 KTS. Not anticipating any severe thunderstorms at this point with a slight uptick in humidity levels with dewpoints in the mid 50s to lower/mid 60s with highs in the upper 70s to lower 80s in the valleys and upper 60s to mid 70s over the higher terrain with partly sunny conditions giving way to mostly cloudy skies in the afternoon.

KEY MESSAGE 2...

A wet and unsettled pattern sets up for next week with mid and upper level ridging upstream over the Upper Midwest, Great Lakes Region and Ontario with the high centered over the lower to mid MS River Valley. A cold front begins to move southward across upstate NY, New England and PA with the west/northwest flow aloft. We have maintained close to the NBM for few showers (isolated to widely scattered) on Monday mainly south and west of the Capital Region. However, the cold front begins to slowly lift back north/northeast, as a warm front Mon night into Tue morning with increasing isentropic lift, and PWATs rising 1 to 2 STDEVs above normal. WPC has a Marginal Risk (Level 1 of 4) in the Day 3 ERO across the region. The locations for any locally heavy rainfall varies in the guidance and ensembles, so low confidence exists and with some dry and rain free days before Monday, so the threat looks lower for flash flooding.

Tue through Wed...Multiple short-waves in the west to northwest flow over the top of the upstream ridge could bring showers and scattered thunderstorms. Some of the thunderstorms could be on the strong to severe side, as the old SPC Day 4 to 8 graphic highlights 15% probabilities of a severe threat for Wed-Wed night with strong mid-level jet aloft of 50 KT or greater, dewpoints in the 60s, ample deep shear (30-40 KT) and instability on the moderate to potentially large side on some of the medium range guidance and ensembles. The area highlighted with the 15% probs is south and west of the Capital Region. Very challenging to time any severe threat this far out. We will continue to monitor trends over the next several days. For Tue and Wed, WPC has a Marginal Risk (Level 1 of 4) in the ERO for an isolated flash threat with periods of locally heavy rainfall with any MCS. The latest 24-hr NBM probabilities for >1" of rainfall across eastern NY and western New England by 12Z/Thu are in the 25-50% range. Timing and placements of the disturbances still vary, which makes the rainfall totals challenging to pinpoint with low confidence this far out. Stayed close to the NBM/WPC guidance with PoPs in the 55-70% range Tue into Wed with a slight to low chance of thunderstorms. Max temps Tue through Thu will be seasonable in the 70s to lower 80s with cooler temps over the higher terrain with lows in the 50s and 60s at night.

AVIATION /06Z SATURDAY THROUGH WEDNESDAY/

Through 06Z Sunday... VFR conditions are expected to prevail across all terminals for this TAF period. There is potential for some mist/fog development in the early morning hours today at KGFL, which could bring brief drops in vis and cigs to IFR, reflected by a TEMPO group. Otherwise, mostly clear skies with a few fair weather cumulus are expected to persist throughout the day. Winds will remain light overall, slightly strengthening in the afternoon, before weakening again after sunset.

Outlook...

Sunday Night: Moderate Operational Impact. Chance of SHRA. Monday: No Operational Impact. NO SIG WX. Monday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Tuesday: High Operational Impact. Likely SHRA...TSRA. Tuesday Night: High Operational Impact. Likely SHRA. Wednesday: High Operational Impact. Likely SHRA...TSRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.